A system and method for using an element made of porous ceramic materials such as zeolite to constrain the flow of gas molecules to the free molecular or transitional flow regime. A preferred embodiment of the gas pump may include the zeolite element, a heater, a cooler, passive thermal elements, and encapsulation. The zeolite element may be further comprised of multiple types of porous matrix sub-elements, which may be coated with other materials and may be connected in series or in parallel. The gas pump may further include sensors and a control mechanism that is responsive to the output of the sensors. The control mechanism may further provide the ability to turn on and off certain heaters in order to reverse the flow in the gas pump. In one embodiment, the pump may operate by utilizing waste heat from an external system to induce transpiration driven flow across the zeolite. In another embodiment, the pump may selectively drive and direct gas molecules depending on the molecular size and the interaction between the gas molecule and the zeolite element.